Just a quick and easy guide for something i picked up just randomly messing around with cars in solo play and here is how you do it.
Other OTWD Guides:
First Find an Alarm Car
Doesnt matter which vehicle it is 1 face the front of it (where you would go to use a power kit) and charge a heavy attack with a machete or pickaxe and follow it up with a light attack right after. Side note ensure you dont hit the bumper aim for the hood of the car the screenshot should be enough to show this.
Hope this helps a few people get that little extra loot they may need in a level to open all their boxes i find this is more useful in solo play than group play but still wanted to share some good info to everyone.